http://repub.eur.nl/res/concept/jel-H54/ Recent publications classified by JEL Code H54 en http://repub.eur.nl/static-eur/img/logo.png http://repub.eur.nl http://repub.eur.nl/res/pub/10460/ 2007-07-04T00:00:00Z We present empirical evidence that stocks with low volatility earn high risk-adjusted returns. The annual alpha spread of global low versus high volatility decile portfolios amounts to 12% over the 1986-2006 period. We also observe this volatility effect within the US, European and Japanese markets in isolation. Furthermore, we find that the volatility effect cannot be explained by other well-known effects such as value and size. Our results indicate that equity investors overpay for risky stocks. Possible explanations for this phenomenon include (i) leverage restrictions, (ii) inefficient two-step investment processes, and (iii) behavioral biases of private investors. In order to exploit the volatility effect in practice we argue that investors should include low risk stocks as a separate asset class in the strategic asset allocation phase of their investment process. Blitz, D.C. Vliet, P. van http://repub.eur.nl/res/pub/7235/ 2005-01-01T00:00:00Z The Dutch national road network has been developed over several decades. In the past, roads were constructed according to the then current spatial and transportation planning philosophies. Because the existing road network is a result of a long process of successive developments, the question can be asked whether this network is the most appropriate from the current point of view, especially taking in consideration the current socio economic structure of the Netherlands. To answer this question an optimization algorithm for designing road networks has been developed. With this algorithm the Dutch road network has been redesigned based on minimization of the travel and infrastructure costs and by taking into account the socio economic structure of the Netherlands. A comparison between the existing network and the new design shows that the redesigned Dutch national road network has significantly lower total costs than the existing road network. It is found that the construction of less roads with more lanes on different locations leads to a reduction of the total travel time and the total vehicles kilometers traveled. Snelder, M. Wagelmans, A.P.M. Schrijver, J.M. Zuylen, H.J. van Immers, L.H.